Retina Today - ILM Peeling in a Detached Retina Without the Use of PFCL (January 2013)

摘要

In this issue of Retina Today, Raju Sampangi, MD, DNB, and B.C. Hemalatha, MS, FMRF, describe a technique for internal limiting membrane peeling in a detached retina without the use of perfluorocarbon liquid. We extend an invitation to readers to submit pearls for publication in Retina Today. Please send submissions for consideration to Dean Eliott, MD (dean_eliott@meei.harvard.edu); or Ingrid U. Scott, MD, MPH (iscott@hmc.psu.edu). We look forward to hearing from you. Internal limiting membrane (ILM) peeling is a challenging step during macular surgery. Various surgeons use different techniques to achieve the desired endpoint. Although ILM peeling is primarily performed in patients with macular hole, it is considered for many other indications. We perform ILM peeling for the following conditions apart from macular hole: (1) chronic diabetic macular edema not responding to intravitreal anti-VEGF or steroid therapy; (2) epiretinal membrane (ERM) in the macular region; (3) significant macular wrinkling but no visible ERM; and (4) chronic or recurrent retinal detachments that have inner retinal wrinkling, retinal stiffness, or apparent intrinsic contracture. Sometimes patients with the aforementioned indications may have associated retinal detachment involving the posterior pole, necessitating ILM peeling in a detached retina. Performing the ILM peel in the presence of posterior pole detachment is more challenging than in an attached retina. This can be attributed to the fact that there is a lack of countertraction when removing the ILM in a mobile detached retina. Perfluorocarbon liquid (PFCL) can be used to stabilize the posterior pole; however, the inherent weight of PFCL can make the initiation of ILM peel difficult. Also, in patients with a large macular hole or myopic macular hole with posterior staphyloma, there is a risk of subretinal migration of PFCL. We initially used PFCL but later observed that it leads to the ILM flap being pressed flat against the retina, and this creates more stress with every attempt to grasp the ILM. These reservations prompted us to try ILM peeling in detached retinas without using PFCL. This article details the steps that we follow when using this technique. For a video demonstration, visit eyetube.net/?v=hoodu STAINING In our initial surgeries, we stained the ILM with trypan blue under air (Figure 1A) and later began using brilliant blue G (Ocublue Plus; Aurolab, India). It is important to remember 2 properties of brilliant blue G dye: it stains ILM well and quickly, without the need for fluid-air exchange, and it stains the vitreous if left for some time. This dye is very useful for identifying vitreoschisis in patients with myopia and patients with diabetes, but it can sometimes mislead one to think that the ILM has been peeled when actually it is a thin posterior hyaloid. We sometimes stain multiple times using very little dye, just 3 to 4 small streams over the area of interest. This helps confirm adequate removal of membranes, especially in patients with diabetes. DRAINING SUBRETINAL FLUID For patients in whom ILM peeling is indicated, if the detachment extends to the midperiphery or beyond, we usually drain the subretinal fluid through a separate retinotomy. This process of flattening the retina may stretch the membranes and help to create some loose areas that may aid in peeling. It also makes the retina less mobile, as the amount of subretinal fluid has been reduced. Even when staining with brilliant blue, one can create a small retinotomy and try a fluid-fluid exchange to reduce the amount of subretinal fluid. INITIATING THE PEEL Where? The most critical part of this step is to lift the initial edge of the ILM. The trick to achieving a good grasp of the ILM is to look carefully at the retinal surface for ILM wrinkling; the ILM is usually loosely attached at the wrinkle, and one can i